Refrigeration apparatus



Oct. 30, 1934.

M. E. HANSON REFRIGERATION APPARATUS Filed Jan. 17, 1934 iiii lii INVEN TOR.

N WQ 0 Y MM um 5 N -01 I H L Y B 555mmU UU E Q UU Patented Oct; 30, 1934 nnrarcnaarron Arr'anarus Milton E. Hanson, Collingswood, N. 1., assignor to B. F. Stnrtevant Company, Inc., Boston,

Application January 17, 1934,, Serial No. 706,940 9 Clalms. (Cl. (3-24) This invention relates to the conditioning of air for human comfort, and relates more particularly to the refrigeration and dehumidification of air circulated through passenger vehicles in sum- 5 mer.

It is now'becoming well known that human com-' fort requires that the air within an enclosure should be not only circulated to provide sufficient ventilation, but should in winter, be warmed, with moisture added to maintain the proper relative humidity, and in summer should be cooled, and moisture extracted from it, to overcome the excessive humidity which isusually present.

While the conditioning of air for motion picture theaters, hotels, oflice and industrial buildings has been developed to a high degree in recent years, the air conditioning of vehicles, and particularly railway cars, has been more or less neglected, due, perhaps, to the peculiar problems involved and the many difliculties present. Among the difllculties which present themselves are the lack of space in a railway car which already of necessity has had to accommodate the maximum of equipment in the minimum of space, the excessive refrigeration equipment which would have to be carried if the ordinary method of conditioning buildings were followed, the changing temperature conditions through which a railway car must pass, the cost of the equipment, and other difiiculties. The weight of refrigerating systems is a serious factor, particularly when this weight must be carried all the year round.

'The cost of mechanical systems of refrigeration are so high, the equipment so bulky, and its weight so great that in many instances, especially on short runs and on long runs where there is an opportunity for re-icing, many railroads have preferred to use ice systems for supplying the necessary cooling effect in railway passenger cars. It is a fact that, while ice has many advantages for air conditioning purposes, such for example as low initial cost and ease of installation, it has the outstanding disadvantages that the amount of ice required is great and on long runs re-icing is required.

According to this invention, air conditioning systems utilizing dry ice for the cooling of air are provided. Dry ice, which is solidified carbon dioxide, has a very low temperature, and/large cooling effect can be obtained from a very small amount of dry ice. While dry ice, at the moment, is relatively expensive, its cost is less than it formerly was, and its cost is continually decreasing due to increasing use of the substance in all classes of refrigeration. Since any commercial air cooling system has to be feasible from an economic standpoint, this inventionprovides for the combined use of dry and ordinary ice.v The ordinary ice may be used alone on short runs, and on long runs ordinary ice may be supplemented with dry ice for enabling the car to reach its destination without reicing.

According to a feature of this invention, a unique form of cooling surface for cooling the air through the use of dry ice is provided.

According to another feature of this invention, means is provided for preventing the freezing of the water in the circulation system.

An object of the invention is to cool air through the use of dry ice. J

Another object of the invention is to adapt a water-ice cooling system for use with dry ice.

Another object of the invention is to provide a. unique form of heat exchange surface between dry ice and the fluid to be cooled thereby.

Another object of the invention is to prevent the freezing up of the water circulation system when the circulating pump is stopped.

Other objects of the invention will be apparent from the following description taken with the drawing.

The invention will now be described with reference to the drawing, of which:

. Fig. 1 is a side view, with a portion in dotted outline, of a railway car equipped with an air conditioning system according to this invention;

Fig. 2 is an end view of the railway car of Fig. 1 with a portion of one end removed to show the air circulatory system employed;

Fig. 3 is an enlarged view, with a portion of z the exterior removed, of the ice bins of Fig. 1.

The railway car of Fig. 1 is equipped with the cartridge fed type of insulated ice bin indicated generally by the numeral 10 and illustrated in detail by Fig. 3. This bin comprises the four doors 11 through which ice, in blocks, is inserted into the bin. Water is sprayed over the ice in the bin andthe melting ice cools the water which is circulated by a pump through the pipe lines, indicated by the dotted hnesin Fig. 1, to and from the cooling units Ill-mounted in each end of the car. These cooling units are each equipped with a blower for indrawing outside and recirculated air, passing the mixed air through the cooler 12, and discharging it into the passenger space. Air is circulated through the passenger space in a ductless system, cooled air being forced down along one side of the car and overhead from one unit towards the other unit, is indrawn by the other unit at the other ill) of the extended surface.

cooling coils through which the refrigerated water'from the ice bin is circulated.

As shown by Fig. 2, the grille 13 indicates the discharge outlet of one of the cooling units 12, and the grille. 14 indicates the recirculated air inlet of the same cooling unit. -At the other end of the car a similar cooling unit is arranged, but with the discharge and intake grilles oppositely arranged. That is, the intake grille of the other unit is arranged opposite the discharge grille'13 of the unit shown by Fig. 2, and the discharge grille of theother unit is arranged opposite the intake grille of the unit shown by Fig. 2.

ing, the valve" 15 is closed and the valve 16 is' open. The reservoir 17 contains water which is indrawn into the intake 20 by the pump 21, driven by the electric motor 22, which is energized from the car lighting system. The water indrawn by the pump is discharged by the pump discharge outlet 23 into the passageway 24, located between the two accordion or bellows type extended surfaces 25 and 26. The ice in the bin rests upon the upper extended surfaces 25, and, of course, after a period of time its lower surfaces, through the action of gravity and temperature, fit down into the V-shaped grooves The water is cooled, when ordinary ice is used, by return water through pipe 19 being fed through the plurality of spray nozzles 27 onto the surfaces of the ice cakes. The water melts the ice and is cooled thereby,.collects in the lower portion of the ice bin defined by the upper extended surfaces 25,

and overflows through the overflow passage 28,.

which is arranged completely around the sides of the ice bin in such a manner that all of the water drains completely out of the lowest portions of the V-shaped passages formed by the extended surfaces 25, into the reservoir 17, and is recirculatedby the pump as before. -The overflow pipe 31 is placed at the return end of the circulating system so that the warmest water in the reservoir 17 is drained to the track as the water level in the reservoir increases due to that added by the melting of the ice.

When dry ice is used, the valve 15 is open and the valve 16 is closed. With the closing of the valve 16, no spray water can flow onto the surfaces .of the dry ice and the entire cooling action is into the V-shaped'notches of the upper [J1 25 and through direct contact with the metal surfaces 25, they, through their very low temperature, extract a considerable amount of heat from the circulating water in the passage 24 through the heat exchange action of the considerable amount of heat exchange surface 24 in contact with the water. It has been found that with this arrangement, dry ice cools satisfactorily the water which is circulated to'the cooling com- I partments in a railway car.

The entire ice bin and the circulating pipes are carefully insulated to avoid heat exchange losses, but the tank 32, to which the intake pipe 20 of the pump .21 is connected, is uninsulated since it is desired that it contain relatively warm water. The tank 32 is separated from the reservoir 17 by the perforated plate 36.

The reservoir 1'7 contains sufiicient water to fill the entire system when the pump 21 starts, and it has been found that even with the ice bin full of dry ice, the surface of the water in the reservoir 17 does not freeze, only a skim of ice being formed. The relatively warm water in the tank 32 does not freeze at all, and when the pump starts, this relatively warm water goes through the chamber 28 and melts any ice that may have been formed on the corrugated floor of the passage 24.

When the pump 21 stops, the electrically controlled valve 33 automatically opens through association with the electrical circuit of the pump and immediately drains the water passage 24 to the reservoir 17 through the drain pipe 34.. The remaining water then may freeze if the pump stops long enough and prevents the freezing of the warm water from the tank 32 melts the ice formed in the lower portion of the passage 24 and the circulating system is again in operation.

If the bin has been filled with dry ice and for any reason it is desired to put in ordinary waterice, it is only necessary to close the valve 15 and open the valve 16, and the system is immediately ready for operation with, ordinary ice.

Again, if it is decided to put.in dry ice, following the consumption or removal of water ice, all of the water that was in-the ice space drains completely out through the passage ,28 into the reservoir 17, leaving the upper surfaces of the extended surface 25 dry and ready for the contact with the dry ice, so, with this change, all that is needed to be done is to close valve 16 and open valve 15.

v Whereas an embodiment of the invention hasbeen described for purposes of illustration, it

should be understood that the invention is not limited to the exact embodiment described, since many modifications may occur to those skilled in the art without departing from the real inventive concept. a

What is claimed is: s '1. An air conditioning system fora passenger vehicle, comprising an air cooling chamber. means for passing air through said chamber where it is cooled and into the passenger space of the vehicle, an ice bin for receiving cakes or ice, a thin metal sheet in said ice bin upon which the stored ice cakes rest, means forming a fluid passage having as its upper wall said sheet, means forming a fluid reservoir, a pump and connections for circulating fluid from said reservoir through said e and to chamber. and

means for draining said passage when said pump is stopped.

2. An air conditioning system for a passenger vehicle, comprising an air cooling chamber, means for passing air through said chamber where it is cooled and into the passenger space of the vehicle, an ice bin for receiving cakes of ice, a corrugated thin metal sheet in said ice bin upon which the stored ice cakes rest, means forming a fluid passage having as its upper wall said sheet, means forming a fluid reservoir, a pump and connections for circulating fluid from said reservoir through said passage and to said cooling chamber, and means for draining said passage when said pump is stopped.

3. An air conditioning system for a passenger vehicle, comprising an air cooling chamber, means for passing air through said chamber where it is cooled and into the passenger space of the vehicle, an ice bin for receiving cakes of ice, a corrugated thin metal sheet in said ice bin upon which the stored ice cakes rest, means forming a fluid passage having as its upper wall said sheet and having as its lower wall another corrugated sheet, means forming a fluid reservoir, a pump and connections for circulating fluid from said reservoir through said passage and to said cooling chamber, and means for draining said passage when said pump is stopped.

4. An air conditioning system for a passenger vehicle, comprising an air cooling chamber, means for passing air through said chamber where it is cooled and into the passenger space of the vehicle, an ice bin for receiving cakes of ice, a thin metal sheet in said ice bin upon which the stored ice cakes rest, means forming a fluid passage having as its upper wall said sheet, means forming a fluid reservoir, a pump and connections for circulating fluid from said reservoir through said passage and to said cooling chamher, and means for draining said passage when said pump is stopped.

5. Anair conditioning system for a passenger vehicle, comprising an air cooling chamber, means for passing air through said chamber where it is cooled and into the passenger space of the vehicle, an ice bin for receiving cakes of ice, 'a corrugated thin metal sheet in said ice bin upon which the stored ice cakes rest, means forming a fluid passage having as its upper wall said sheet, means forming a fluid reservoir, a pump and connections for circulating fluid from said reservoir through said passage and to said cooling chamber, and means for automatically draining said passage when said pump is stopped.

6. An air conditioning system for a passenger vehicle, comprising an air cooling chamber, means for passing air through said chamber where it is cooled and into the passenger space or the vehicle, an ice bin for receiving cakes or ice, a corrugated thin metal sheet in said ice bin upon which the stored ice cakes rest, means forming a fluid passage having as its upper wall said sheet, means forming a fluid reservoir, a warm fluid compartment connecting with said reservoir, and a pump and connections for circulating the fluid from said compartment through said passage and to said cooling chamber.

7. An air conditioning system for a passenger vehicle, comprising an air cooling chamber, means for passing air through said chamher where it is cooled and into the passenger space of the vehicle, an ice bin for receiving cakes of ice, a corrugated thin metal sheet in said ice bin upon which the stored ice cakes rest, means forming a fluid passage having as its upper wall said sheet, means forming a fluid reservoir, a warm fluid compartment connecting with said reservoir, a pump and connections for circulating the fluid from said compartment through said passage and to said cooling chamber, and means for draining said passage when said pump is stopped.

8. An air conditioning system for a passenger vehicle, comprising an air cooling chamber, means for passing air through said chamber where it is cooled and into the passenger space of the vehicle, an ice bin for receiving cakes of ice, a thin metal sheet in said ice bin upon which the stored ice cakes rest, means forming a fluid passage having as its upper wall said sheet, means forming a fluid reservoir, a pump and connections for circulating fluid from said reservoir through said passage and to said cooling chamber,

spray nozzles for spraying the fluid returned from said chamber upon said ice cakes, a return pipe from. said chamber to said spray nozzles, a valve in said pipe adjacent said spray nozzles, a second return pipe to said reservoir, and a valve in said second return pipe.

9. An air conditioning system for a passenger vehicle, comprising an air cooling chamber, means for passing air through said chamber where it is cooled and into the passenger space of the vehicle, an ice bin for receiving cakes of ice, a thin metal sheet in said ice bin upon which the stored ice cakes rest, means forming a fluid passage having as its upper wall said sheet, means forming a fluid reservoir below said passage, a pump and connections for circulating fluid from said reservoir through said passage and to said cooling chamber, spray nozzles for spraying the fluid returned from said chamber upon said ice cakes, a return pipe from said chamber to said spray nozzles, a valve in said pipe adja- .3.

cent said spray nozzles, a second return pipe to said reservoir, a valve in said second return pipe, and means for draining said passage when said pump is stopped.

MILTON E. HANSQN. 

